Andrew Mountbatten-Windsor has been arrested and is in custody on suspicion of misconduct in public office.
Thames Valley Police say officers are carrying out searches at the former prince’s addresses in Berkshire and Norfolk.
In a statement, the police said: “As part of the investigation, we have today (19/2) arrested a man in his sixties from Norfolk on suspicion of misconduct in public office and are carrying out searches at addresses in Berkshire and Norfolk.
“The man remains in police custody at this time.
“We will not be naming the arrested man, as per national guidance. Please also remember that this case is now active so care should be taken with any publication to avoid being in contempt of court.
“Assistant Chief Constable Oliver Wright said: “Following a thorough assessment, we have now opened an investigation into this allegation of misconduct in public office.
“It is important that we protect the integrity and objectivity of our investigation as we work with our partners to investigate this alleged offence.
“We understand the significant public interest in this case, and we will provide updates at the appropriate time.”
This arrest comes following investigations into a complaint over the alleged sharing of confidential material by Andrew with the sex offender Jeffrey Epstein.
The King’s brother, who turns 66 today, has strongly denied any allegations of wrongdoing.
Andrew, who turns 66 today, has strongly denied any allegations of wrongdoing.
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